Question

why mathematicians came up with words like "and", "or", "not", "implies", "if and only if", "exist", "for all".

Answer 1

idk. just seems natural and logical

Answer 2

but, we must know

Answer 3

It just came naturally from our ability of thinking

Answer 4

there is something to be with human cognition?

Answer 5

So that they could algebraically manipulate statements in a logical way.

Answer 6

maybe.

Answer 7

how we can investigate that?

Answer 8

I think that's the kind of question better answered at math stackexchange

Answer 9

where is that?

Answer 10

http://math.stackexchange.com/

Answer 11

cute site

Answer 12

hmm... true. but the real question is: why not zoidberg?

Answer 13

openstudy is cuter comparing to math stackexchange lol...

Answer 14

this site has many questions i cannot answer...

Answer 15

Probably were used as placeholder words as everything else, but then they just went with it, instinct, arbitrary, natural, could be any.

Answer 16

like why not zoidberg?

Answer 17

All of these are just things we can say about statements that can be answered with a yes or no.

If I say:

"You are happy."

"Your teeth are brown."

then we can combine them and say:

"you are happy" AND "your teeth are brown." as one sentence.

Now with these specific words we can say that this statement is exactly the same as

"you are not happy or your teeth are not brown" has the same answer as the last question because they are identical. This is called a tautology.

Answer 18

#best reply

Answer 19

Here, let's let P="You are happy" and Q="Your teeth are brown."

Then if P or Q is true or false we'll put a T or F next to it. So we can say things like: So this is all 4 possible cases. Either both are true, P is true and Q is false, the other way around, or they're both false. With me so far?